Nonmyeloablative allogeneic stem cell transplantation for patients with unresectable pancreatic cancer

To clarify whether nonmyeloablative allogeneic stem cell transplantation (NST) can produce the graft versus tumor (GVT) effect in patients with pancreatic cancer.

A pilot trial of NST was conducted in 5 patients with unresectable pancreatic cancer. Preparative conditioning consisted of administration of 60 mg/kg cyclophosphamide on days 6 and 7 before transplantation, followed by 25 mg fludarabine per square meter of body surface on each of the last 5 days prior to transplantation. Cyclosporine was started 4 days before transplantation. Peripheral blood stem cells from the patients' HLA-identical siblings were transfused into the patients.

Complete donor T-cell chimerism in peripheral blood was obtained in 4 patients on day 15 after transplantation. NST resulted in tumor reduction in 2 patients as determined by CT, decreasing levels of tumor markers in 2 patients, pain relief in 2 patients, and a decrease in pleural fluid in 1 patient. Two patients developed acute graft versus host disease (GVHD) of grade II or III and 2 had chronic GVHD involving skin and/or liver. Administration of immunosuppressive drugs for the treatment of GVHD resulted in the elevation of tumor marker levels.

These findings are the first to suggest that NST induces a GVT effect on pancreatic cancer.